In the figure given below, Q is a chemical substance that can be detected by sensory organs P and R. Which of the following most probably represents P and R? (i) The nose (ii) The ear (iii) The tongue

• A.                                                          Only (i) and (ii)
• B.  Only (i) and (iii)               
• C.  Only (ii) and (iii)
• D.         (i), (ii) and (iii)