Answer:
The plus end for all actin filaments.(Ans. A)
Explanation:
All three types of muscles (cardiac, smooth, and skeletal) utilize actin filaments to generate force which leads to cell contraction. Actin filaments is organized into sarcomeres which function as the fundamental unit of contraction.
Sarcomeres are approx 2.4 micro meter in length, and they are bounded at both end with the help of Z-disks. Plus end of the Z-disks are oriented with actin filaments and their minus ends to the direction of center of the sarcomeres. Z-disk consist an actin capping protein, which is known as cap-Z. Cap-Z helps to bind plus end of the actin filaments.
 
        
             
        
        
        
Different environment cause different species to "<span> Become more diverse" this process is known as "Adaptation" which changes the characteristic of an organism according to its environment
In short, Your Answer would be Option A
Hope this helps!</span>
        
                    
             
        
        
        
✧・゚: *✧・゚:*    *:・゚✧*:・゚✧
                   Hello!
✧・゚: *✧・゚:*    *:・゚✧*:・゚✧
❖ The correct answer is classification. 
~ ʜᴏᴘᴇ ᴛʜɪꜱ ʜᴇʟᴘꜱ! :) ♡
~ ᴄʟᴏᴜᴛᴀɴꜱᴡᴇʀꜱ