Select the most appropriate option to fill in the blank.

The situation turned ugly as the crowd ______ to riot.

began

The most appropriate option to fill in the blank is:

☀ began

The sentence would read: "The situation turned ugly as the crowd began to riot."

Explanation: The word "began" is the correct past tense form of the verb "begin," which is used to indicate the start of an action. In this context, it shows that the crowd started to riot, leading to the situation turning ugly. The other options don't fit the context:

• Begins: This is the present tense form and doesn't fit the past tense context.

• Begun: This is the past participle form and doesn't work as the main verb in this sentence.

• Beginning: This is the gerund form and doesn't fit the context of the sentence.