In Kent's Repertory, the "Generalities" section includes symptoms that affect the whole organism or are not specific to any particular part. Let's examine each rubric:
\begin{itemize}
\item (A) Bed sores: This is a localized skin condition due to pressure and would be found under the "Skin" chapter.
\item (B) Thrombosis: This refers to the formation of blood clots within blood vessels and is a general pathological state affecting the circulatory system, thus found under "Generalities."
\item (C) Apoplexy: Also known as stroke, this is a sudden neurological impairment due to vascular issues in the brain, considered a general pathological condition and listed under "Generalities."
\item (D) Constipation amel.: This refers to the general condition of constipation with a stated amelioration (amel.), indicating a general modality affecting the bowel function and thus found under "Generalities."
\item (E) Diarrhoea in aged people: While it specifies an age group, diarrhoea itself is a symptom related to the digestive system and would be primarily found under the "Stool and Rectum" chapter, possibly with age-related sub-rubrics there, rather than as a main generality.
\end{itemize}
Therefore, the rubrics that are typically found in the "Generalities" section of Kent's Repertory among the given options are Thrombosis, Apoplexy, and Constipation amel.