The external characteristic for the dc series generator is?

• A. <a href="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-questions-answers-operating-characteristics-dc-generator-q12a.png"><img alt="The external characteristic for the dc series generator - option a" class="alignnone size-full wp-image-160824" height="245" src="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-questions-answers-operating-characteristics-dc-generator-q12a.png" width="300"/></a>
• B. <a href="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-questions-answers-operating-characteristics-dc-generator-q12b.png"><img alt="The external characteristic for the dc series generator - option b" class="alignnone size-full wp-image-160825" height="224" src="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-questions-answers-operating-characteristics-dc-generator-q12b.png" width="300"/></a>
• C. <a href="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-questions-answers-operating-characteristics-dc-generator-q12c.png"><img alt="The external characteristic for the dc series generator - option c" class="alignnone size-full wp-image-160826" height="216" src="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-questions-answers-operating-characteristics-dc-generator-q12c.png" width="276"/></a>
• D. <a href="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-questions-answers-operating-characteristics-dc-generator-q12d.png"><img alt="The external characteristic for the dc series generator - option d" class="alignnone size-full wp-image-160827" height="238" src="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-questions-answers-operating-characteristics-dc-generator-q12d.png" width="284"/></a>