In the following sentence, a portion of the text is highlighted and may contain a grammatical error. Select the option that best substitutes the highlighted portion to make the sentence grammatically correct. If the original sentence is correct, select “No improvement needed”.

Just as with physical fitness, achieving solid financial security comes down to the minor, deliberate choices he makes by his career.

The correct option to substitute the highlighted portion is "deliberate choices he makes over".

Step-by-Step Explanation:

1. Analyzing Preposition Usage:
In the original sentence, the phrase "choices... by his career" uses the incorrect preposition "by". When talking about making choices across or throughout the span of a career or lifetime, the appropriate preposition is "over" (e.g., "choices he makes over his career").

2. Evaluating Adjective vs. Adverb:
The word modifying "choices" needs to be an adjective because "choices" is a noun. "Deliberate" is an adjective, whereas "deliberately" is an adverb. Therefore, "deliberately choices" is grammatically incorrect.

3. Consistency of Tense and Context:
The sentence describes a general, ongoing principle ("Just as with physical fitness, achieving solid financial security comes down to..."). Thus, the simple present tense "makes" correctly aligns with "comes down to", maintaining parallelism and consistency in tense.

Combining these corrections yields the grammatically sound phrase: "deliberate choices he makes over".