The correct answer should be A. Whomever.
This is because this can be paraphrased as "the instructor has picked him" not "the instructor has picked he". Him corresponds to whomever while he corresponds to whoever.

Context clues are clues in the text that surround a word. You can use them to understand the meaning of the word.
Another example besides the one provided is “She thought the computer was profitless, but it turned out to be very <em>valuable</em>.”
Using context clues such as the word “<em>valuable</em>,” you can get a good idea of what the word “profitless” means.
Answer:
was and skiing
skiing is the helping verb
yesterday is the participle
Explanation:
When you preview something, you inspect it. Previewing helps you get a glimpse of what's ahead before you read or something, kind of like skimming.
I'm confused to what the question is?