Match List-I with List-II.
| List-I | List-II |
|---|---|
| (a) Aspergillus niger | (i) Acetic acid |
| (b) Acetobacter aceti | (ii) Lactic acid |
| (c) Clostridium butylicum | (iii) Citric acid |
| (d) Lactobacillus | (iv) Butyric acid |
Choose the correct answer from the options given below: