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 is deliberate choices he makes over.

Step-by-step Explanation:

1. Analyzing the Context and Preposition:
The original sentence uses the phrase "choices he makes by his career". In English grammar, the preposition "by" is incorrect when expressing choices made throughout or across the duration/span of something like a career. The appropriate preposition to express decisions or actions made across a period of time or course of development (such as a career) is "over" (i.e., "choices he makes over his career").

2. Evaluating the Adjective and Noun Agreement:
- "deliberate" is an adjective correctly modifying the noun "choices". Using an adverb like "deliberately" before a noun (as in "deliberately choices") is grammatically incorrect.
- The plural noun "choices" logically matches "minor, deliberate choices" because achieving financial security involves multiple ongoing decisions over time.

3. Tense Consistency:
The sentence establishes a general truth/principle in the present tense ("comes down to"). Therefore, the present tense verb "makes" is appropriate and consistent with the general nature of the statement.

Combining these corrections, the proper phrase is "deliberate choices he makes over".