Which sentence has titles that are punctuated correctly?

a. I found the recipe in a “New York Times” article called A Spoonful of Spring Asparagus, Green as Can Be.
b. I found the recipe in a “New York Times” article called “A Spoonful of Spring Asparagus, Green as Can Be.”
c. I found the recipe in a New York Times article called “A Spoonful of Spring Asparagus, Green as Can Be.”
d. I found the recipe in a New York Times article called “A Spoonful of Spring Asparagus, Green as Can Be.