Concept:
This question tests our understanding of phrasal verbs. A phrasal verb is formed when a verb combines with a preposition or an adverb to create a meaning different from the meaning of the individual words.
The sentence provides an important contextual clue: heavy rain. Because of bad weather, a scheduled meeting could not take place as planned. Therefore, we need a phrasal verb that means to cancel an event.
The sentence structure:
\[
\text{The meeting was _ _ _ _ }
\]
also indicates a passive construction, which requires a past participle form.
Step 1: Understanding the context of the sentence.
The sentence states that there was heavy rain.
When severe weather conditions occur, meetings, matches, ceremonies, and public events are often postponed or cancelled.
Therefore, the missing phrasal verb should express the idea of cancellation.
Step 2: Evaluating each option carefully.
• called of
This expression is grammatically incorrect because the correct phrasal verb is call off, not call of.
Therefore, this option is incorrect.
• called up
The phrasal verb call up generally means to telephone someone, summon someone, or bring something to mind.
It does not mean to cancel an event.
Therefore, this option is incorrect.
• calling off
The phrasal verb call off indeed means to cancel.
However, the sentence requires a past participle after the auxiliary verb “was.”
The form “calling off” is grammatically incorrect in this structure.
Therefore, this option is incorrect.
• called off
The phrasal verb call off means to cancel an event, meeting, match, or activity.
The past participle form “called off” correctly fits the passive construction.
Therefore, this is the correct answer.
Step 3: Forming the complete sentence.
Substituting the correct option gives:
\[
\text{Owing to heavy rain, the meeting was called off.}
\]
The sentence is grammatically correct and logically meaningful.
Hence,
\[
\boxed{\text{called off}}
\]
is the correct answer.