When several phrases are combined, a usually results.

When several phrases are combined, a sentence usually results. The options were:

So, the correct answer is "sentence". Because many phrases make up one sentence.

A phrase is when words can be grouped together, but without a subject or a verb. Phrases can be short or long. And you can use phrases as part of a sentence (they are used as parts of speech). A complete sentence has a subject and predicate. Complex sentences can combine multiple phrases to add additional information about what is described.

answer; chemical substances that affect our psychological state;