Which behavior is most likely to carry risk of serious infection

Using IV drugs

Explanation:

IV drugs are drugs injected directly into the user's vein. Because people who use this type of drug share the same needle and usually with no antiseptic attitude, this type of drug provides a high risk of infection. Contact with body fluids of a person with some kind of infection represents a direct contagion of this infection. Thus, as IV drug users use a single needle, they come into contact with each other's blood and spread the infection.

depression is an ongoing sadness\lack of motivation. you feel and feel like its never going to get better. you're so sad to the point you think of death.

anxiety is an ongoing feeling of paranoia\ feeling like everyone is watching you and making fun of you. you get nervous easily and feel like the room is spinning.  

yes, they cause death every year. its a long, exhausting battle. only few make it through as sad as it sounds.

explanation:

answer: proteins

explanation: complement is   system of circulate in the blood in a inactive form

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