Option (A) is the correct answer.
There are two types of articles:
DEFINITE ARTICLE (THE): Article 'the' is used to refer to a DEFINITE thing or person. INDEFINITE ARTICLE(A/AN): Article 'a/an' is used to refer to a thing or person in general. For instance: man, door, etc.
Article 'a' is used with consonant sounds whereas article 'an' is used with vowel sounds.
In the first blank, article "a" will be used as it is written 'American Polar Traveller' and it is a general noun.
In the second blank, article "the" will be used because article "the" is used when with ordinals such as "first", "second" T, etc and it is given that 'he was first to reach.' Similarly, 'North Pole' is a proper noun (something unique). Therefore, in the third blank, article "the" will be used.