Angel has been sending English learning videos . . . . . July 2014.

Solution (By Examveda Team)

Since: This word is used to indicate the starting point of an action or event that continues into the present. It is typically used with a specific point in time (e.g., "since Monday," "since 2010").

Correct Answer: Option A - since
The sentence is: "Angel has been sending English learning videos . . . . . July 2014."

This sentence is in the present perfect continuous tense, which is used to show that an action started in the past and is still continuing. The word that follows the blank, "July 2014", is a specific point in time (not a duration).

In English grammar, when we refer to the starting point of a continuing action, we use the word "since". Therefore, the correct sentence should be:
"Angel has been sending English learning videos since July 2014."

Why the other options are incorrect:
Option B: for – "For" is used to express a duration of time (e.g., "for two years"). Since "July 2014" is a point in time, not a duration, "for" is incorrect here.
Option C: from – "From" usually requires a second point in time (e.g., "from July 2014 to December 2016"). Alone, it is grammatically incomplete in this context.
Option D: in – "In" is used to indicate that something happened during a certain time period, but it doesn’t convey the idea of continuity. It would change the meaning of the sentence.

Conclusion:
The correct answer is since because it properly matches the tense and structure of the sentence, referring to the starting point of a continuous action.