1. Databricks Documentation
Data visualization in Databricks: While not providing a formal definition
the documentation states that a histogram "plots the frequency distribution of a numeric column." This directly supports the use case in the question
where histograms are created for continuous (numeric) variables. (See: Databricks Documentation > Visualizations > Histogram).
2. PennState
STAT 200: Elementary Statistics Courseware: In Lesson 1.2
"Types of Variables
" a continuous variable is defined as "a quantitative variable that has an infinite number of possible values that are not countable." This directly supports option C.
3. MIT OpenCourseWare
18.05 Introduction to Probability and Statistics
Spring 2014: The class notes for "Topic 2: Discrete and Continuous Variables" define a continuous random variable as one whose set of possible values is an entire interval of numbers
which is an uncountable set. This aligns perfectly with the correct answer. (See: MIT OCW
18.05
Topic 2 Notes
Section 1).