Find out whether there is any grammatical error in below sentence.Another reason for pharmaceutical companies beefing up their / OTC (Over the Country) divisions is that prescription drugs with proven safety records which have been reached / the end of the their patent protection periodare

• A. OTC (Over the Country) divisions is that prescription drugs with proven safety records which have been reached
• B. Another reason for pharmaceutical companies beefing up their
• C. the end of the their patent protection periodare
• D. allowed to be sold without a prescription. No error

Answer: (A)