Read the following statements and select the correct option
Statement A: Alveoli are the primary sites of exchange of gases which consist of single thin layer of flattened cells with irregular boundaries
Statement B: Thin, permeable of gases, moist and least vascular are come of the characters of a typical respiratory surface
1. Both statements (A) and (B) are correct
2. Both statements (A) and (B) are incorrect
3. Only statement (A) is correct
4. Only statement (A) is incorrect