## Core Concept
The question pertains to the sequence of bacterial invasion in dental caries or oral infections, specifically focusing on the role of *Streptococcus mutans* (*S. mutans*). *S. mutans* is a primary colonizer of tooth surfaces and plays a significant role in the initiation of dental caries due to its ability to produce acid from fermentable carbohydrates.

## Why the Correct Answer is Right
The correct sequence involves *S. mutans* as an early colonizer. In the process of oral biofilm formation and dental plaque development, *S. mutans* adheres to tooth surfaces, facilitating the accumulation of other bacteria. *Lactobacillus* species often invade or become more prominent in areas where caries are progressing, as they are also acidogenic and aciduric. However, the specific sequence provided in the question and correct answer isn't directly addressed without more context. Generally, *S. mutans* is followed by other bacteria like *Lactobacillus*, *Actinomyces*, and various anaerobic bacteria in the progression of dental caries and periodontal diseases.

## Why Each Wrong Option is Incorrect
- **Option A:** Without specific details on the bacteria listed in A, B, C, or D, we can't directly assess their accuracy. However, if *Lactobacillus* or other bacteria are listed as preceding *S. mutans*, they would be incorrect because *S. mutans* is typically considered an early colonizer.
- **Option B:** Similarly, if this option suggests a sequence where *S. mutans* is not a primary colonizer or doesn't precede the listed bacteria, it would be incorrect.
- **Option C:** This option might list a correct sequence or a plausible succession of bacteria in oral infections but isn't the correct answer based on the information given.
- **Option D:** If this option accurately describes bacteria that invade after *S. mutans*, it would align with the correct sequence of microbial succession in the oral cavity.

## Clinical Pearl / High-Yield Fact
A key point to remember is that *Streptococcus mutans* is a crucial bacterium in the development of dental caries due to its acidogenic and aciduric properties. The progression of dental caries involves a shift in the microbial composition of dental plaque, often from *S. mutans* and other streptococci to more aciduric bacteria like *Lactobacillus*.

## Correct Answer: D.