Which of the following fungus is an ovoid, budding yeast which is of 3-5 microns in diameter containing elongated filamentous cells joined end to end?
**Core Concept**
The question is testing the student's knowledge of the morphological characteristics of various fungi, specifically the distinction between yeast forms and filamentous forms.
**Why the Correct Answer is Right**
The correct answer is a type of fungus that exhibits a unique combination of yeast and filamentous growth. In this particular organism, the yeast cells are ovoid in shape, approximately 3-5 microns in diameter, and exhibit budding. The presence of elongated filamentous cells, which are joined end to end, is a distinctive feature of this organism. This morphology is characteristic of **Candida albicans**, a species of fungus that is commonly found on human mucosal surfaces and can cause opportunistic infections in immunocompromised individuals.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not match the description provided. The wrong organism might be a type of fungus that is primarily filamentous, such as Aspergillus or Mucor.
* **Option B:** This option is also incorrect because it does not match the description. Another type of fungus, such as Cryptococcus neoformans, might exhibit a similar yeast-like morphology but lacks the distinctive filamentous cells.
* **Option D:** This option is incorrect because it does not match the description provided. A different type of fungus, such as Histoplasma capsulatum, might exhibit a yeast-like morphology but lacks the distinctive filamentous cells.
**Clinical Pearl / High-Yield Fact**
Candida albicans is a common cause of opportunistic infections in immunocompromised individuals, particularly those with HIV/AIDS or undergoing chemotherapy. It can cause a range of infections, including oral thrush, esophageal candidiasis, and invasive candidiasis.
**Correct Answer:** C. Candida albicans.