Which of the following is a complete sentence?

A.
When I was young and loved going for runs in the park.

B.
I walked all three dogs around the park this morning.

C.
Running through the park before breakfast

D.
Walking with a limp as a result of the thorn

The complete sentence is “I walked all three dogs around the park this morning”, as it expresses complete thought the correct option is B.

A complete sentence requires both a subject and a predicate that express a complete thought. In option B, “I” is the subject, and “walked all three dogs around the park this morning” is the predicate that expresses a complete thought.

Option A is a phrase, not a complete sentence, as it is missing a predicate to express a complete thought. Option C is also a phrase, as it does not have a predicate that expresses a complete thought. Option D is a dependent clause, which requires an independent clause to form a complete sentence, the correct option is B.