The correct answer is B. On Wednesday, Senator Richardson met with members of the United Nations.
Explanation:
In grammar, capitalization refers to the use of uppercase in the first letter of a word, according to grammar this should be used in the first word of a text or after a period, in names and in proper nouns including days, months and holidays, brands of products or similar, institutions or organization, planets, government titles if they are before the proper names, streets, and roads, among others. This implies in the case of the sentence presented the words that should be capitalized are "On" because this is the first word in the sentences; "Wednesday" because this is the name of a day and therefore a proper noun; "Senator Richarson" because this is part of a government title and in this case it precedes the proper noun "Richarson" which means both words should be capitalized and the words "United Nations" because this is the name of an organization. Considering this, the sentence that shows the correct capitalization is "On Wednesday, Senator Richardson met with members of the United Nations".
