Under the Basel I framework, banks are required to hold a minimum Total capital of 8% of risk-weighted assets (RWA), with at least half of this being Tier 1 capital (i.e., Tier 1 capital > 4% of RWA). Total capital is simply the sum of Tier 1 capital and Tier 2 capital.

Therefore:

• A is a correct expression, representing the minimum Tier 1 capital requirement.
• B is a correct expression, representing the minimum Total capital requirement.
• C is a correct expression, representing the definition of Total capital.
• D is an incorrect expression, because the sum of Tier 1 and Tier 2 capital equals Total capital, it is not greater than Total capital.