Context: Mohinder gasped softly as he watched the serum disappear from the tube and into his veins . It felt strange for a few moments after ... tingly . Mohinder wondered how he 'd test it , then he thought that he could at least take a sample of his own blood to see if anything had changed within . Quickly , he rushed back inside but in his excitement to see the results of his experiment -- he tripped and his body started to head straight for the tall glass window .

Question: What may have caused Mohinder to trip ?
Options:
0. Mohinder slipped on his own blood .
1. He injected a known substance directly into his veins .
2. None of the above choices .
3. The strange substance intoxicated him .
Answer: 3