Why is formalin dangerous for humans body.

I’m going to guess these are the choices: a) recreational skiing developed in the mid-19th century b) it was originally invented as a way of getting from place to place in snowy regions c) downhill skiing is currently the only common form of the sport d) it mostly evolved from snowshoeing- if that’s the cases then the answer would be c) downhill skiing is currently the only common form of the sport

Yes, most genetic diseases can not be cured. usually it can be treated. just like hereditatary prostate and breast cancer. so may i know what the choices are? the choices could not be found in your question. : )