With reference to bio-toilets used by the Indian Railways, consider the following statements:1.The decomposition of human waste in the bio-toilets is initiated by a fungal inoculum.2.Ammonia and water vapour are the only end products in this decomposition which are released into the atmosphere.Which of the statements given above is/are correct?

1. A

   1 only

   Statement 1 is false. Indian Railways bio-toilets use a bacterial (anaerobic) inoculum developed with DRDE, not a fungal inoculum. ‘1 only’ is not the key.

2. B

   2 only

   Statement 2 is false. Anaerobic digestion yields methane, carbon dioxide and water, among other residues; ammonia and water vapour are not the only end products, nor are they simply vented as the sole outputs. This option is therefore wrong.

3. C

   Both 1 and 2

   Both statements fail. This option is not the key.

4. D

   Neither 1 nor 2

   Neither statement is correct: the inoculum is bacterial, and the gas/water story in statement 2 is wrong. This option is the official key.

Summary. Official key is (d) Neither 1 nor 2. Bio-toilets on Railways rely on anaerobic bacteria that digest human waste in tanks under the coach. Fungi are not the starter culture. End products include biogas (methane and CO2) and treated effluent, not ‘only ammonia and water vapour’. Both claims therefore fall.