The correct option to complete the sentence is:
a. "Is helping, starts"
Explanation:
👉 "Is helping" is the continuous present tense form, and "starts" is the simple present tense form of the respective verbs.
👉 The sentence talks about an ongoing action in the present ("Charles is helping his father") and a future action ("school starts").
👉 This option appropriately indicates that Charles is currently helping his father and that school will commence at a future time.
👉 The verb tense agreement ensures consistency between the current action and the future action being described.
