[Solution from source] Protonation of the alkene gives the secondary carbocation (CH₃)₃C–C⁺H–CH₃, which undergoes a 1,2-methyl shift to the more stable tertiary carbocation (CH₃)₂C⁺–CH(CH₃)₂. Water attacks this to give 2,3-dimethylbutan-2-ol, (CH₃)₂C(OH)–CH(CH₃)₂. The unrearranged alcohol (CH₃)₃C–CH(OH)–CH₃ is the minor product. Answer (2).