As British scientist Peter Whibberley has observed, “The Earth is not a very good timekeeper.” Earth’s slightly irregular rotation rate means that measurements of time must be periodically adjusted. Specifically, an extra “leap second” (the 86,401st second of the day) is____time-based on the planet’s rotation lags a full nine-tenths of a second behind time kept by precise atomic clocks.

Which choice completes the text so that it conforms to the conventions of Standard English?

A short passage explicit the information to analyze, and interpret the main idea.

Special attention to the facts and details draws out the main idea.

Can you summarize what you’ve understood in the above steps?

Choice A is correct because this option correctly introduces a conditional clause with "whenever," indicating the specific condition under which the leap second is added. It maintains proper sentence structure and punctuation

added whenever

Choice B is incorrect because it improperly places a comma before "whenever," disrupting the flow and clarity of the sentence.

added,whenever

Choice C is incorrect because the period (.) between "added" and "whenever" is incorrect in Standard English. When forming a compound word like "added whenever," it should not be separated by a period.

added.whenever

Choice D is incorrect because it disrupts the logical order and flow of the sentence, creating confusion.

whenever,added

The most logical text for the given passage

added whenever

Option

A

Can you summarize what you’ve understood in the above steps?