A 28-year-old male presents with elevated mood, decreased need for sleep, grandiosity, and increased activity lasting >1 week, impairing social function. What is the diagnosis?

Correct option is A

Bipolar I requires ≥1 manic episode (≥1 week, marked impairment). Bipolar II has hypomania (less severe, no marked impairment).
Explanation of options: (a) ✔ Correct; classic manic episode = Bipolar I. (b) ✘ Bipolar II = hypomania + depression, no full mania. (c) ✘ Schizoaffective = psychosis with mood disorder. (d) ✘ Cyclothymia = mild fluctuations, no mania.