Which sentence contains coordinate adjectives that should be separated by commas

A the slinky tabby cat backed slowly away from the fence as the dog barked
B I played on the best softball team in my town
C the bus hot crowded and loud so we decided to get off and walk
D seven large swans came swimming by all at once startling the ducks

C the bus hot crowded and loud so we decided to get off and walk

The sentence that contains coordinate adjectives that should be separated by commas is:

C) The bus was hot, crowded, and loud, so we decided to get off and walk.

The sentence that contains coordinate adjectives that should be separated by commas is:

D) Seven large swans came swimming by all at once, startling the ducks.

To determine if coordinate adjectives should be separated by commas, we can check if both adjectives can independently modify the noun. In this case, "large" and "swans" can individually modify the noun "swans." Therefore, they are coordinate adjectives and should be separated by commas.