Maria (60) is hoping to start receiving social security benefits as early as possible, in the next couple of years. She has a qualifying self-only insurance plan and is already contributing $1,000 a year to her HSA but wants to maximize her contributions in anticipation of retirement. How much more can she contribute to her HSA for 2021?

A) $1,000

B) $2,600

C) $3,600

D) $6,200