This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Social & Preventive Medicine
Which of the following is not an example of direct transmission in communicable diseases ? 
Select and explain. 
A. Transplacental (veical), B. Soil, C. Respiratory, D. STD
C: Respiratory
Answer: C: Respiratory 
Explanation: The modes of transmission of infectious diseases can be classified as: * Direct Transmission. Direct contact; Droplet infection; Contact with soil; Inoculation into skin or mucosa; Transplacental (veical)transmission. * Indirect Transmission. Vehicle-borne; Water; food/milk; Vector-borne. Mechanical; Biological. Airborne. ENT ref : park 21st ed