Every single time we use the internet, we leave behind a detailed trail of data: what we search for, what we buy, where we go, and whom we choose to talk to. Companies now collect and analyze this personal information on an absolutely enormous scale, mainly in order to sell advertising more effectively. For a long time, this was widely seen as little more than a matter of personal privacy. In recent years, however, more and more people have begun to ask whether the vast collection of personal data also poses a real threat to democracy itself.
One major concern is the way in which data can be used to influence people's opinions. By gathering detailed information about millions of individuals, political groups can target particular people with carefully crafted messages designed to appeal directly to their own personal fears and hopes. Different voters may therefore see completely different messages, each one tailored precisely to them and hidden from everyone else. Critics worry that this quietly makes honest, open public debate far harder, since citizens are no longer all responding to the same shared body of information.
There is also the very real danger of constant surveillance. When governments or large companies are able to monitor closely what ordinary people read, say, and do, individuals may slowly become afraid to express unpopular opinions or to seek out certain kinds of information at all. This so-called "chilling effect" can quietly weaken the open exchange of ideas on which any healthy democracy ultimately depends. Even if no one is ever directly punished, the mere knowledge that one is constantly being watched can be enough to change how people behave.
Responses to these growing concerns vary widely from place to place. Some countries have introduced strong new laws giving people much more control over their own personal data and strictly limiting how it can be collected and used. Others rely mainly on the companies themselves to set sensible limits. Defenders of large-scale data collection argue that it brings real and valuable benefits, from useful free services to economic growth, and that heavy-handed rules could do genuine harm. The central challenge, many now believe, is to enjoy the obvious advantages of a data-rich world while firmly protecting the privacy and freedom that a healthy democracy truly requires.
（1） 正解 2. Because it may pose a threat to democracy itself.
第1段落末に「個人データの大量収集が民主主義そのものへの脅威となるのではないか」とある。選択肢2。
（2） 正解 2. By targeting people with tailored messages hidden from others.
第2段落に「個人に合わせ、他人には隠されたメッセージで人々を狙う」とある。選択肢2。
（3） 正解 2. People become afraid to express opinions when watched.
第3段落に「見張られていると、不人気な意見を述べるのを恐れるようになる」とある。選択肢2。
（4） 正解 2. Some pass strong laws, while others rely on self-regulation.
第4段落に「強い法律を導入した国もあれば、企業の自主規制に頼る国もある」とある。選択肢2。
underestimate：過小評価する
to think something is smaller or less important than it is（実際より小さい・重要でないと考える）
vivid：鮮烈な
producing strong, clear images in the mind（心に強く鮮明な像を生む）
invasive：侵入性の
spreading harmfully into a new area（新しい地域に有害に広がる）
biodiversity：生物多様性
the variety of living things in an area（ある地域の生き物の多様さ）
decipher：解読する
to work out the meaning of something unclear（不明瞭なものの意味を解き明かす）
script：文字（体系）
a system of written characters（書かれた文字の体系）
surveillance：監視
the close watching of people（人々を注意深く見張ること）
monitor：監視する
to watch and check over time（時間をかけて見守り点検する）