Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
If winner is alejandro Valverde and the points Classification is by Erik Zabel, who is the mountain classification?

### Inputs:
table_name: table, columns: ['Stage', 'Winner', 'General classification', 'Points classification', 'Mountains classification', 'Combination classification', 'Team classification']

### Response:
SELECT Mountains classification FROM table WHERE Winner = Alejandro Valverde AND Points classification = Erik Zabel