The little girl in a red dress cautiously danced a waltz.
The adverb(s) and/or adverb phrase(s) in the sentence is/are .

(A) in a red dress only
(B) cautiously only
(C) both in a red dress and cautiously

Cautiously.

Explanation:

Cautiously is an adverb (base adjective cautious with -ly ending) modifying 'danced'  (telling how she danced).

"In a red dress" is a prepositional phrase. Some prepositional phrases can be adverb phrases, but in this sentence this prepositional phrase is an adjective phrase. It helps describe and identify the noun, 'girl.'

gold miners!

explanation: