Step 1: Understand the use of articles in English.
Articles (a, an, the) are used before nouns to specify whether the noun is definite or indefinite.
'A' is used before singular countable nouns that begin with a consonant sound.
'An' is used before singular countable nouns that begin with a vowel sound.
'The' is used before specific or particular nouns, whether singular or plural, countable or uncountable. Step 2: Identify the noun following the blank.
The noun following the blank is "actress". Step 3: Determine the sound of the initial letter of the noun.
The word "actress" begins with the vowel sound /æ/. Step 4: Choose the appropriate article.
Since "actress" starts with a vowel sound, the indefinite article "an" should be used. (1) an