Life insurance written to cover a need for a specified period of time at the lowest premium is called:

Endowment 65 is a type of life insurance that combines elements of both insurance and investment. It typically matures when the insured individual reaches the age of 65, providing a lump sum payment or annuity. This type of policy is not specifically focused on covering a need for a defined period at the lowest premium.

20-pay Life insurance requires the policyholder to pay premiums for a limited period, usually 20 years, after which the policy remains in force for the insured's lifetime. While the premium payments are limited to 20 years, this type of insurance does not necessarily cater to covering a specific need for a specified period at the lowest premium.

Permanent Life insurance provides coverage for the entire lifetime of the insured individual, as long as premiums are paid. Unlike term insurance, permanent life policies do not have a specific term limit and often include a cash value component. This type of insurance focuses on lifelong coverage rather than meeting a temporary need at the lowest premium.