Mo. Rev. Stat. § 400.2-601: Buyer's rights on improper delivery.

Subject to the provisions of this article on breach in installment contracts (section 400.2-612) and unless otherwise agreed under the sections on contractual limitations of remedy (sections 400.2-718 and 400.2-719), if the goods or the tender of delivery fail in any respect to conform to the contract, the buyer may

(a) reject the whole; or

(b) accept the whole; or

(c) accept any commercial unit or units and reject the rest.