Which of the following individuals is eligible for Medicare benefits? Choose all individuals that are eligible.

John who is $70$ and continues to work full$-$time at an advertising agency.

Lisa who is $62,$ just retired from teaching, and recently started taking early social security benefits.

Kelly who is $35,$ works at a university, and has permanent kidney failure.

Jeff who is $45,$ works part$-$time, and is disabled. He has been receiving social security disability benefits for two years.