Sentence A — "The ideal solution will be to advertise aggressively." — This is a recommendation and opinion, hence Judgement (J).
Sentence B — "One brand is already popular amongst the youth." — This is a verifiable statement about brand popularity, making it a Fact (F).
Sentence C — "Reducing prices will mean trouble as our revenues are already dwindling." — This is a deduction from the stated fact that revenues are dwindling, making it an Inference (I).
Sentence D — "The correct solution will be to consolidate by aggressive marketing." — This is another opinion/recommendation, hence Judgement (J).
Thus, the classification is: J (A), F (B), I (C), J (D) → JFIJ.