When drive-ins were at the height of their popularity in the late 1950's, some 4,000 existed in the United States, but today there are less than one-quarter that many.

• Athere are less than one-quarter that many  
• Bthere are fewer than one-quarter as many  
• Cthere are fewer than one-quarter of that amount  
• Dthe number is less than one-quarter the amount  
• Eit is less than one-quarter of that amount