The TLV values of four pollutants A, B, C and Dare 9ppm, 10ppm, 100ppm and 500 ppm respectively. The most toxic amount them is

The TLV values of four pollutants A, B, C and Dare 9ppm, 10ppm, 100ppm

1.	The TLV values of four pollutants A, B, C and Dare 9ppm, 10ppm, 100ppm and 500 ppm respectively. The most toxic amount them is
Answer» A B C D Answer :A