Select the most appropriate option to fill in blank number 1.
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. widely.
"Widely" means something that is broadly known or recognized.
"Widely" here means to a great extent or by many people. In this passage, it refers to the Big Bang theory being accepted by most scientists.
Meaning of the other words:
Vastly: By a very large amount.
Largely: For the most part, mainly.
Loosely: Not strictly or tightly.
Hence, the chosen option is correct.