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

### Instruction:
Which owner has a description of Mark 1 pos and is dated 1956?

### Inputs:
table_name: table, columns: ['Number & Name', 'Description', 'Livery', 'Owner(s)', 'Date']

### Response:
SELECT Owner(s) FROM table WHERE Date = 1956 AND Description = mark 1 pos