Question: For which UTRA FDD UE categories is the MIMO performance test for HS-DSCH in multi-path fading environments mandatory, according to Release 10 and later releases?
Option 1: HSDPA UE capability categories 12 - 15
Option 2: HSDPA UE capability categories 20 - 24
Option 3: HSDPA UE capability categories 25 - 28
Option 4: All HSDPA UE capability categories
Explanation: The correct answer is Option 3 because the MIMO performance test requirements for High Speed Physical Downlink Shared Channel (HS-DSCH) in multi-path fading environments specifically apply to Release 10 and later releases for UTRA FDD UE supporting HSDPA UE capability categories 25 - 28.