Which sentence uses punctuation correctly?

a. there are thousands of species of colorful native wildflowers in
eastern north america, and only eleven species have orange
flowers.
b. there are thousands of species of colorful native wildflowers in
eastern north america, only eleven species have orange flowers.
c. there are thousands of species of colorful native wildflowers in
eastern north america only eleven species have orange flowers.
d. there are thousands of species of colorful native wildflowers in
eastern north america; only eleven species have orange flowers.