What is the size of a chlorophyll molecule?

• A
  Head $15 \times 15 \, \mathring A$,Tail $25 \, \mathring A$
• B
  Head $20 \times 20 \, \mathring A$,Tail $25 \, \mathring A$
• C
  Head $15 \times 15 \, \mathring A$,Tail $20 \, \mathring A$
• D
  Head $10 \times 12 \, \mathring A$,Tail $25 \, \mathring A$