Which of the following can be threats to the biodiversity of a geographical area? 1. Global warming 2. Fragmentation of habitat 3. Invasion of alien species 4. Promotion of vegetarianism Select the correct answer using the codes given below :

1. (a)1, 2 and 3 only
2. (b)2 and 3 only
3. (c)1 and 4 only
4. (d)1, 2, 3 and 4