The first clues of a biological incident include which of the following? (Select all that apply.) Select one or more:

a. Unscheduled and unusual spray being disseminated

b. An outbreak of psoriasis

c. Abandoned spray devices

d. Unusual numbers of sick or dying pe

The answer is 'D' - Unusual number of sick or dying people.

Explanation:

Biological incident can be defined as diseases which occur naturally in humans or are spread through terrorist motives. There are lot of red flags which should be noticed before the disease reaches a peak limit.

The first sign of a biological incident will be reported by the medical authorities as there will be a large number of people getting sick or dying.

Either the deaths will be caused due to spread of a communicable disease or a biological agent has been released on purpose.