He <em><u>had forgotten</u></em> to take his umbrella.
The above Underlined phrase <em><u>'</u></em><em><u>had</u></em><em><u> </u></em><em><u>forgotten</u></em><em><u> </u></em><em><u>'</u></em> is in <em>Past Perfect Tense.</em>
A sentence style employed by
Hemingway that uses many conjunctions is called polysyndeton. The answer is
letter B. The conjunctions are repeated in close successions and some could be omitted
due to the repetition.