Kim Has a Written Contract with Eddie's Snowplows for Snow

Kim has a written contract with Eddie's Snowplows for snow removal of snow from around his store. The contract is in effect "until the end of the winter". There are two unexpected snowfalls towards the end of April, and Eddie charges Kim extra for clearing the snow on those two occasions. Kim's position is that "winter" continues until the last snowfall of the year. Besides, although they didn't write it in the contract, Eddie told Kim not to worry if the winter lasted longer than usual, he'd take care of it. Eddie told that to his other customers in the area too. What do you think is the likely result if this dispute goes to court? Why?

A) Kim will not have to pay. The contra proferentem rule applies against Eddie's interpretation of the contract.
B) Eddie was entitled to charge extra. The dictionary says that winter ends at the beginning of spring, which is in March.
C) Kim will not have to pay. The contract is ambiguous with respect to this term, so what Eddie said to Kim and the other customers is admissible to interpret it.
D) Eddie was entitled to charge extra. The court cannot look outside the four corners of the contract to see if "winter" means something other than "winter".
E) Eddie was entitled to charge extra. The custom of the trade is that snowplowers quit by mid-April at the latest.