This is a test of commonsense with single/multi-choices. Complete the next sentence:

How to buy rv batteries
Look for a battery at an auto parts store.
The chassis battery in your rv serves the same purpose as the automotive battery in any vehicle. These batteries can be purchased at your local auto parts stores and usually cost between $50 and $300, depending on the type of battery you choose and the brand.

Choices: [I] For example, if you are looking for a 2005 hp battery, you should go for about $100 for your battery. Look for a battery that is dual powered.. [II] Determine how you would like to take your battery at a discount. Different battery types are used for different purposes.. [III] Some battery brands, such as edmunds, customizable, and dell batteries, may also sell for about $200 or more usd. Check for diatomaceous earth batteries.. [IV] Ask the clerk at the front desk to look up your rv in their system to offer you suggestions about the battery options you have. Some large retailers also have automotive sections you can purchase chassis batteries in..
The answer is:
[IV]