What would happen if the earth magnetic field flips? plz

The end of the world as we know it could come in any number of ways, depending on who you ask. Some people believe global cataclysm will occur when Earth's magnetic poles reverse. When north goes south, they say, the continents will lurch in one direction or the other, triggering massive earthquakes, rapid climate change and species extinctions.

The most dramatic changes that occur when the poles reverse is a very large decrease of the total field intensity,

Earth's magnetic field takes between 1,000 and 10,000 years to reverse, and in the process, it greatly diminishes before it re-aligns. It's not a sudden flip, but a slow process, during which the field strength becomes weak, very probably the field becomes more complex and might show more than two poles for a while, and then builds up in strength and [aligns] in the opposite direction.

substituting a hydrogen atom with a halogen in a hydrocarbon:

- the single bond remains single. a is wrong.

- the bond with hydrogen is as strong as with a halogen. c is wrong

- a hydrocarbon is saturated if there is no double bond. we do not know that so d is wrong.

- carbon will always have four valence electrons. e is wrong.

by elimination, the correct answer is b. the boiling point of the new compound increases.