The correct Active/Passive form of the given sentence is:

☀ You should carefully deal with this matter.

So, the correct active form is: "You should carefully deal with this matter."

The other options and their explanations:

☀ You should deals with this matter carefully.

• This option contains a grammatical error. The correct form is "deal" (base form) instead of "deals" (present tense) when using "should."

☀ You should be carefully dealing with this matter.

• This option is in the active voice but changes the sentence structure and meaning. It suggests that "you" are already dealing with the matter carefully, rather than being advised to do so in the future.

☀ You should carefully be dealt with this matter.

• This option is not grammatically correct. The correct form is "deal with this matter" instead of "dealt with this matter" to match the original sentence. Additionally, the passive voice is not necessary here, as the original sentence is already in the passive voice.