In the following question a short passage is given with one of the lines in the passage missing and represented by a blank. Select the best out of the five answer choices given, to make the passage complete and coherent.

Obesity is mainly caused when the intake of the calories exceed the dissipated calories. In simple words, when one tends to eat more than his body requirement, the extra fat start depositing in the body tissues giving rise to obesity. Junk food is the main culprit. Children are fond of such unhealthy food items and hence are getting more affected by the rising incidences of obesity. The other common cause is the lack of physical activity. ______. But the modern day sedentary life style leaves less time to work out. Thence, lack of exercise is a major contributing factor. However, in certain cases a plateau phase has been noticed. This generally occurs due to hormonal imbalance mainly caused by disturbance in physiological system of the body. Genetic predisposition also plays a major role as a causative factor.