1. This was an important day for Alan.
P. It was a cold day, but Alan would be warm.
Q. For the first time he was going to hunt seals alone.
R. First he put on his fur-lined jacket.
S. Then he put on mittens and boots of deerskin to protect his hands and feet from the cold.
6. Finally he picked up the gun he had cleaned so carefully the day before.

The correct answer is option number -B

1st sentence-This was an important day for Alan.

Connectors from Part Q to Part P-

Connectors-For the first time he was going to hunt seals alone.

Sentence Q connects sentence P

Sentence Q-tells that for Alan it was an important day.Since pronoun `He' is used in other sentences,first sentence should mention the name.Option,Q is hence the correct choice.

The next sentence should explain why it is an important day for Alan 

Only sentence `P'  explains that 

For the 1st time he was going for hunting alone.

Connectors from Part P to Part R

Connectors-It was a cold day, but Alan would be warm

Connectors-First he put on his fur-lined jacket.

Now,only one option is remaining-

Then he put on mittens and boots of deerskin to protect his hands and feet from the cold

Last sentence will be -

Finally he picked up the gun he had cleaned so carefully the day before.

The correct sequence is therefore-QPRS.