A company's ecommerce website is experiencing massive traffic spikes, which are causing performance problems in the company database. Users are reporting that accessing the website takes a long time. A developer wants to implement a caching layer using Amazon ElastiCache. The website is required to be responsive no matter which product a user views, and the updates to product information and prices must be strongly consistent. Which cache writing policy will satisfy these requirements?

A $.$ Which cache writing policy will satisfy these requirements?

B $.$ Write to the cache directly and sync the backend at a later time.

C $.$ Write to the backend first and wait for the cache to expire.

D $.$ Write to the cache and the backend at the same time

E $.$ Write to the backend first and invalidate the cache