A contract provided, On January 5, Purchaser shall provide Seller with a certified check in the amount

Question:

A contract provided, On January 5, Purchaser shall provide Seller with a certified check in the amount of $100,000. Seller shall transfer a deed for the Property to Purchaser." What is wrong with this provision?
(a) It is not clear who Purchaser and Seller are.
(b) The number $100,000 should be written in words.
(c) The promises are reciprocal.
(d) The promises are conditional.