Read the statements and choose the correct option. Statement A: Busy is an adjective but business is an abstract noun. Statement B: A sentence starting with a common noun should not start with a capital letter. Statement C: Constellation is a material noun but star is a common noun. Statement D: Common nouns can sometimes be used as proper nouns.

• A. (A) and (B) are correct.             
• B. (B) and (D) are correct.
• C. (C) and (D) are correct.              
• D. (A) and (C) are correct.