。
She's Mr. Uda's secretary.
Literal
She [topic-は] Mr.-Uda [genitive-の] secretary is.
宇田氏 uses the suffix 氏 ('Mr./Ms./Mx.'), a formal honorific name suffix used in writing — newspapers, official records, business correspondence — when さん would feel too informal. 氏 also functions as a stand-alone pronoun ('the said person') in legal or journalistic writing. As a suffix it doesn't distinguish gender. 秘書 ('secretary') refers to the executive-assistant kind of role rather than office support broadly: 秘書 implies a senior assistant to a high-ranking person, often a politician (議員秘書) or company executive. The polite copula です gives the introduction a tidy, professional feel.