Cyufjy

I am traveling to Jamaica via a US port. Since Jamaica has on arrival visa for Indian citizens, do I need a transit visa for the USA? My next flight from the USA is 4 hours later.

You are an Indian national travelling to Jamaica. You are making a transfer in the USA. To transit in the US, you need a C-1 visa.

If you are a non-US citizen and are merely passing through the United
States while transiting to another foreign country, a C-1 transit visa
is an appropriate non-immigrant visa. If you are traveling with your
family, each person regardless of age, even children and babies listed
in parents' passports, needs to apply for a separate C-1 Visa. Persons
from the countries that qualify for the Visa Waiver program can
transit to the US without a transit visa.

An immigration officer at the port of entry can admit a person holding
a C-1 transit visa for the duration determined by him/her, but for a
maximum duration of 29 days. You must leave the U.S. on the proposed
flight or ship of departure, or within 29 days, whichever is earlier.
You must pass in immediate and continuous transit through the U.S.

A transit visa is particularly very useful if you need to change
airports in the U.S. Even if you don't need to change the airport, if
there is a long delay before you can board your flight to the final
destination, instead of waiting in the airport, you can get out and
tour the nearby places, visit friends or family members, or do
shopping.

However, even if you are planning to stay in the U.S. even for a day,
you should apply for the B1/B2 visa.

It seems strange that your only choice is a visa which allows you to leave the airport, but okay. I would advise that you avoid transferring in the US if you don't want to deal with the hassle of a visa application and an interview.

Info obtained from here.