Considering language use in the text, it’s correct to say:

✂️ a) The possessive adjective “their” (l. 2) refers to “Fitness trackers” (l. 1)

✂️ b) The expression “so far” (l. 3) is synonymous with up till now.

✂️ c) The verb form “asked” (l. 7) is in the past tense.

✂️ d) The conjunction phrase “either [...] or” (l. 7-9) expresses condition.

✂️ e) The modal “may” (l. 15) expresses necessity.

Responda: Considering language use in the text, it’s correct to say: