| Examples of chemicals produced by plants as a defense against grazers and browsersI. NicotineII. CaffeineIII. QuinineIV. StrychnineV. OpiumChoose the correct combination |
| a) | I and II | b) | I, II, III and IV |
| c) | I, II and III | d) | I, II, III, IV and V |
| (d)A wide variety of chemical substances that we extract from plants on a commercial scale (nicotine, caffeine, quinine, strychnine, opium etc); are produced by them actually as defences against grazers and browsers |