(A) - "furthermore" (II) → Adds another ability to driving; shows he can both drive AND fix cars.
(B) - "however" (III) → Shows contrast between going shopping and not buying anything; indicates an unexpected outcome.
(C) - "henceforth" (IV) → Indicates what happened subsequently; after boosting her morale, she then sang.
(D) - "therefore" (I) → Shows cause and effect; his interest in computers logically results in being called a tech wizard.
Hence, Option 2: (A) - (II), (B) - (III), (C) - (IV), (D) - (I) → The connectors properly establish the logical relationships: addition (furthermore), contrast (however), temporal sequence (henceforth), and causation (therefore) → correct