Answer:
a. The buyer would cover all shipping and insurance costs and assume the risk at the factory door.
Step-by-step explanation:
According to the given situation the exworks means that the seller fulfill his duty for delivering the goods when the goods are available at his place i.e. works, factory or warehouse to the buyer. Also the buyer would responisble to bear all the cost and the risk involved while taking the goods from the seller place to the final destination
Hence, the option a is correct