Step 1: Understanding the Question:
The question tests the categorization of various clinical signs of pregnancy into Presumptive, Probable, and Positive groups.
Step 2: Detailed Explanation:
Presumptive Signs: These are subjective symptoms felt by the woman, such as amenorrhea, nausea, and vomiting. They "suggest" pregnancy but can be caused by other conditions.
Probable Signs: These are objective physiological and anatomical changes observed by an examiner.
The "bluish vagina" (Chadwick's sign) is a classic probable sign due to increased vascularity. Linea nigra (skin hyperpigmentation) and positive pregnancy tests are also categorized as probable.
Positive (Confirmed) Signs: These are absolute evidence of a fetus. They include fetal heart sounds (via Doppler), visualization of the fetus on ultrasound, and fetal movements felt by a clinician.
Analysis: While amenorrhea and nausea are presumptive, the objective physical findings like the bluish vagina (Chadwick's) and skin changes shift the diagnosis into the "Probable" category. None of these signs independently confirm a live pregnancy.
Step 3: Final Answer:
Collectively, these clinical findings are classified as Probable signs of pregnancy.