Help pls:( Which situation describes parasitism?

Parasitism is where a parasite lives on some living beings and proceed to take their advantage.

Example

A parasite controls a bug's body. This is classified as a Parasitism.

A parasite sucks blood. This is also classified as a Parasitism.

Parasitism is basically one living gets the advantage while the another living gets disadvantage.

From the choice, the answer is C because the ticks live on the cow and suck their blood, giving the cow disadvantage. The cow will slowly die and if the cow dies, the ticks will find a new one or die if they don't find any livings to live on.

answer : haversian

[explanation: -(compact bone is organized as parallel columns, known as haversian systems, which run lengthwise down the axis of long bones. these columns are composed of lamellae, concentric rings of bone, surrounding a central channel, or haversian canal, that contains the nerves, blood vessels, and lymphatic system of the bone)]

the question isn't complete here so i can't right an answer '_'