Why might a baby be born early if the mother smokes?

Smoking during pregnancy has a number of problems for the mother and the baby. Often, smoking during pregnancy leads to miscarriage or premature birth of the baby. The weight of the baby is also lower as compared to the babies whose mothers do not smoke during pregnancy. As the conditions inside the mother are not safe of the mother smokes, hence babies are often born early for such mothers. The placental might detach early from the uterine tube.  

correct answer: understand the different control methods available

integrated pest management is an strategy that is based on the ecosystem and try to prevent the pest and the damage caused by them by applying combination of technique like habitat manipulation, biological control and use of resistant varieties.

the main aim of the integrated pest management is not to completely eliminate the pest but to strengthen the ecosystem so that conditions are favorable for plants and unfavorable for pests.